We're back, now, at 7:41, with "Gma" investigates. How to survive deadly rip currents. Over the holiday weekend, hundreds of swimmers had to be rescued from rip currents, that come on suddenly and... See More
We're back, now, at 7:41, with "Gma" investigates. How to survive deadly rip currents. Over the holiday weekend, hundreds of swimmers had to be rescued from rip currents, that come on suddenly and sweep even the strongest swimmer out to sea. Reporter: You probably won't know there's a rip current until you're in it. Only trained eyes can spot them. But you'll feel it pull you away from shore. So, this morning, we go into the waters to show you how to survive. On this Florida beach, a shocking number. 120 people plucked from rip currents Monday alone. It is pretty strong out there, for the little kids to go out there in. Reporter: 250 rescues in central and south Florida in just the past 2 days. Officials say more than 100 people drown every year in the U.S. Because of rip currents. A lot of the people that come to coastal cities on vacation don't have -- have never heard of rip currents. Reporter: When waves break fiercely at the shore, a stream of water moving away from the beach can form. Even Michael Phelps couldn't swim out of those rip currents. Reporter: Most of us aren't Michael Phelps. So, we will show you how to survive. That's where the rip current is. I went right into the rough waters. Then, still near shore, it's pulling. It's really pulling. Just a few minutes to get out here. And now, we're starting to feel it. I intentionally try to swim back to shore directly against the current. That's exactly what you shouldn't do. That's hard. That's hard. Realizing I'm tired, the lifeguards don't take any chances. Give me your left hand. Reporter: You see yourself getting tired. You feel your heart racing. And with all of the waves and B water hitting you. Reporter: To show you the right technique, I go back in. Instead of swimming directly towards shore, we're going to swim diagonally. In a rip current, it's best to swim parallel to shore. I got out of it. I swam diagonally. Even though it's weak, you could feel it. You can still feel it pulling you out. A strong swimmer, a grown man like you, it's not so much of a problem. But when you have little kids, people that have never been to the ocean, that's when it's a problem. Reporter: That's why you should swim at a beach with lifeguards. If you're caught in a rip, the key is, don't panic. Stay calm. And we're told, you should never try to rescue someone else if you're not trained. You'll risk your own life. You just want to swim horizontally, parallel to the shore. Better to swim out a little bit. The staying calm part is the tough part. Thanks for the tips. Really good tips. And speaking of ripped --
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